Forward Error Correction (FEC) is a common method of achieving data transmission with low error rates. FEC coding techniques transmit data in encoded form by encoding the data with added redundancy or parity data, which is used by a decoding device to detect and correct errors introduced during transmission or passage of the data between a source and a destination. Generally, data does not have to be retransmitted to correct errors.
The ability of FEC systems to correct errors without retransmission makes them suitable for use in satellite communications systems. Many satellite communications systems use a conventional form of FEC coding; concatenated Viterbi and Reed Solomon coding. Convolutional encoding with Viterbi decoding is capable of correcting disperse, scattered errors, as caused, for example, by white noise. Reed Solomon (block) coding is capable of correcting limited-size burst errors, as caused, for example, by pulsed noise or fast fading. In combination, concatenated convolutional and Reed Solomon coding improve system performance in the presence of pulse and scattered interference.